By default ASP.NET MVC uses ContentResult for controller method that return result not inherited from actionresult type. That is why if we will return some poco entity it will be only its type name.
Could I overload something in controller to make it return jsonresult by default.
Example:
// return json product representation instead of product typename
public MyController: Controller
{
public Product MyAction()
{
return new Product { Name = "Foo", ID = 1 };
}
}
Best regards,
Alexey Z.
Why not just return a JSonResult?
public ActionResult MyAction()
{
return Json( new Product { Name = "Foo", ID = 1 } );
}
You can decorate your controller with an attribute like this one:
public class ReturnJsonAttribute : ActionFilterAttribute
{
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
var result = filterContext.ActionDescriptor.Execute(filterContext, filterContext.ActionParameters);
filterContext.Result = new JsonResult {Data = result};
}
}
Related
we are writing some API which required sessionId in header and some other data in body.
Is it possible to have only one class automatically parsed partially from header and from body?
Something like:
[HttpGet("messages")]
[Produces("application/json")]
[Consumes("application/json")]
[Authorize(Policy = nameof(SessionHeaderKeyHandler))]
public async Task<ActionResult<MessageData>> GetPendingClockInMessages(PendingMessagesData pendingMessagesRequest)
{
some body...
}
with request class like:
public class PendingMessagesData
{
[FromHeader]
public string SessionId { get; set; }
[FromBody]
public string OrderBy { get; set; }
}
I know, it is possible to do this, but it means, that I have to pass SessionId into the other methods as a parameter, instead of pass only one object. And we would have to do that in every API call.
public async Task<ActionResult<MessageData>> GetPendingClockInMessages(
[FromHeader] string sessionId,
[FromBody] PendingMessagesData pendingMessagesRequest)
{
some body...
}
Thank you,
Jakub
we are writing some API which required sessionId in header and some other data in body. Is it possible to have only one class automatically parsed partially from header and from body
Your GetPendingClockInMessages is annotated with a [HttpGet("messages")]. However, a HTTP GET method has no body at all. Also, it can't consume application/json. Please change it to HttpPost("messages")
Typically, SessionId is not passed in header of Session: {SessionId} like other HTTP headers. Session are encrypted via IDataProtector. In other words, you can't get it by Request.Headers["SessionId"].
Apart from the above two facts, you can create a custom model binder to do that.
Since the Session doesn't come from header directly, let's create a custom [FromSession] attribute to replace your [FromHeader]
public class FromSessionAttribute : Attribute, IBindingSourceMetadata
{
public static readonly BindingSource Instance = new BindingSource("FromSession", "FromSession Binding Source", true, true);
public BindingSource BindingSource { get { return FromSessionAttribute.Instance; } }
}
And since you're consuming application/json, let's create a binder as below:
public class MyModelBinder : IModelBinder
{
private readonly JsonOptions jsonOptions;
public MyModelBinder(IOptions<JsonOptions> jsonOptions)
{
this.jsonOptions = jsonOptions.Value;
}
public async Task BindModelAsync(ModelBindingContext bindingContext)
{
var type = bindingContext.ModelType;
var pis = type.GetProperties();
var result= Activator.CreateInstance(type);
var body= bindingContext.ActionContext.HttpContext.Request.Body;
var stream = new System.IO.StreamReader(body);
var json = await stream.ReadToEndAsync();
try{
result = JsonSerializer.Deserialize(json, type, this.jsonOptions.JsonSerializerOptions);
} catch(Exception){
// in case we want to pass string directly. if you don't need this feature, remove this branch
if(pis.Count()==2){
var prop = pis
.Where(pi => pi.PropertyType == typeof(string) )
.Where(pi => !pi.GetCustomAttributesData().Any(ca => ca.AttributeType == typeof(FromSessionAttribute)))
.FirstOrDefault();
if(prop != null){
prop.SetValue( result ,json.Trim('"'));
}
} else{
bindingContext.ModelState.AddModelError("", $"cannot deserialize from body");
return;
}
}
var sessionId = bindingContext.HttpContext.Session.Id;
if (string.IsNullOrEmpty(sessionId)) {
bindingContext.ModelState.AddModelError("sessionId", $"cannot get SessionId From Session");
return;
} else {
var props = pis.Where(pi => {
var attributes = pi.GetCustomAttributesData();
return attributes.Any( ca => ca.AttributeType == typeof(FromSessionAttribute));
});
foreach(var prop in props) {
prop.SetValue(result, sessionId);
}
bindingContext.Result = ModelBindingResult.Success(result);
}
}
}
How to use
Decorate the property with a FromSession to indicate that we want to get the property via HttpContext.Sessino.Id:
public class PendingMessagesData
{
[FromBody]
public string OrderBy { get; set; } // or a complex model: `public MySub Sub{ get; set; }`
[FromSession]
public string SessionId { get; set; }
}
Finally, add a modelbinder on the action method parameter:
[HttpPost("messages")]
[Produces("application/json")]
[Consumes("application/json")]
public async Task<ActionResult> GetPendingClockInMessages([ModelBinder(typeof(MyModelBinder))]PendingMessagesData pendingMessagesRequest)
{
return Json(pendingMessagesRequest);
}
Personally, I would prefer another way, i.e, creating a FromSessionBinderProvider so that I can implement this without too much effort. :
public class FromSessionDataModelBinder : IModelBinder
{
public Task BindModelAsync(ModelBindingContext bindingContext)
{
var sessionId = bindingContext.HttpContext.Session.Id;
if (string.IsNullOrEmpty(sessionId)) {
bindingContext.ModelState.AddModelError(sessionId, $"cannot get SessionId From Session");
} else {
bindingContext.Result = ModelBindingResult.Success(sessionId);
}
return Task.CompletedTask;
}
}
public class FromSessionBinderProvider : IModelBinderProvider
{
public IModelBinder GetBinder(ModelBinderProviderContext context)
{
if (context == null) { throw new ArgumentNullException(nameof(context)); }
var hasFromSessionAttribute = context.BindingInfo?.BindingSource == FromSessionAttribute.Instance;
return hasFromSessionAttribute ?
new BinderTypeModelBinder(typeof(FromSessionDataModelBinder)) :
null;
}
}
(if you're able to remove the [ApiController] attribute, this way is more easier).
I m new to Azure Function. I m used to code with WebApi where I have an ActionExecutingContext which helps to validate the ModelState.
I created an ActionFilterAttribute which do it automatically:
[AttributeUsage(AttributeTargets.All, AllowMultiple = false)]
public class ValidateModelStateAttribute : ActionFilterAttribute
{
public override void OnActionExecuting(ActionExecutingContext context)
{
if (!context.ModelState.IsValid)
{
//Do something
}
}
}
How can I do that or something similar with Azure function?
For example with this DTO with a name property set as Required:
public class TestDto
{
[Required]
public string Name { get; set; }
}
I created an easy extension which validate the object and set an out parameter with the collection of errors.
public static class ObjectExtensions
{
public static bool IsValid(this object o, out ICollection<ValidationResult> validationResults)
{
validationResults = new List<ValidationResult>();
return Validator.TryValidateObject(o, new ValidationContext(o, null, null), validationResults, true);
}
}
So in my Azure function, here is what I have:
[FunctionName("Create")]
public async Task<IActionResult> CreateAsync(
[HttpTrigger(AuthorizationLevel.Anonymous, "post", Route = "test/")] TestDto dto,
CancellationToken cts,
ILogger log)
{
if (!dto.IsValid(validationResults: out var validationResults))
{
return new BadRequestObjectResult($"{nameof(TestDto)} is invalid: {string.Join(", ", validationResults.Select(s => s.ErrorMessage))}");
}
var result = await _testManager.CreateAsync(new Test() { Name = dto.Name }, cts);
return new OkObjectResult(result);
}
I think you could also write a custom attribute for this that implements the OnExecutingAsync and perform the validation in there, see https://www.c-sharpcorner.com/article/do-you-know-azure-function-have-function-filters/
I need to create a custom action filter attribute, that contains in it a declaration of 2 other filters.
For example:
[ContainsTwoFilters]
public ActionResult Index()
{
return View();
}
Instead of:
[Filter1]
[Filter2]
public ActionResult Index()
{
return View();
}
Desperate for your help.
Thanks.
You can't just inherit your filter in your ContainsTwoFilters becouse FilterAttribute is class and there is no multiple class inheritance in C#.
What you can do is to call all methods of Filter1 and Filter1 that you need inside your ContainsTwoFilters.
Something like this:
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, Inherited = true, AllowMultiple = false)]
public class ContainsTwoFilters : ActionFilterAttribute
{
private Filter1Attribute filter1;
private Filter2Attribute filter2;
public ContainsTwoFilters()
{
//Init filters
filter1 = new Filter1Attribute();
filter2 = new Filter2Attribute();
}
public void OnAuthorization(AuthorizationContext filterContext)
{
//Here we can call 2 filters
filter1.OnAuthorization(filterContext);
filter2.OnAuthorization(filterContext);
}
public override void OnActionExecuting(ActionExecutingContext actionContext)
{
//And here only one
filter2.OnActionExecuting(actionContext);
}
}
Note that if you annotate your method like this:
[ContainsTwoFilters]
[Filter2]
public ActionResult Index()
{
return View();
}
Your Filter2 methods will be called twice. Be carefull.
I'm new to NHibernate and trying to use it in ASP.NET WEB API. Firstly I used it successfully with one table named "Category" which the controller class is as follow:
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using TestMVCProject.Web.Api.HttpFetchers;
using TestMVCProject.Web.Api.Models;
using TestMVCProject.Web.Api.TypeMappers;
using TestMVCProject.Web.Common;
//using TestMVCProject.Web.Common.Security;
using NHibernate;
namespace TestMVCProject.Web.Api.Controllers
{
[LoggingNHibernateSession]
public class CategoryController : ApiController
{
private readonly ISession _session;
private readonly ICategoryMapper _categoryMapper;
private readonly IHttpCategoryFetcher _categoryFetcher;
public CategoryController(
ISession session,
ICategoryMapper categoryMapper,
IHttpCategoryFetcher categoryFetcher)
{
_session = session;
_categoryMapper = categoryMapper;
_categoryFetcher = categoryFetcher;
}
public IEnumerable<Category> Get()
{
return _session
.QueryOver<Data.Model.Category>()
.List()
.Select(_categoryMapper.CreateCategory)
.ToList();
}
public Category Get(long id)
{
var category = _categoryFetcher.GetCategory(id);
return _categoryMapper.CreateCategory(category);
}
public HttpResponseMessage Post(HttpRequestMessage request, Category category)
{
var modelCategory = new Data.Model.Category
{
Description = category.Description,
CategoryName = category.CategoryName
};
_session.Save(modelCategory);
var newCategory = _categoryMapper.CreateCategory(modelCategory);
//var href = newCategory.Links.First(x => x.Rel == "self").Href;
var response = request.CreateResponse(HttpStatusCode.Created, newCategory);
//response.Headers.Add("Location", href);
return response;
}
public HttpResponseMessage Delete()
{
var categories = _session.QueryOver<Data.Model.Category>().List();
foreach (var category in categories)
{
_session.Delete(category);
}
return new HttpResponseMessage(HttpStatusCode.OK);
}
public HttpResponseMessage Delete(long id)
{
var category = _session.Get<Data.Model.Category>(id);
if (category != null)
{
_session.Delete(category);
}
return new HttpResponseMessage(HttpStatusCode.OK);
}
public Category Put(long id, Category category)
{
var modelCateogry = _categoryFetcher.GetCategory(id);
modelCateogry.CategoryName = category.CategoryName;
modelCateogry.Description = category.Description;
_session.SaveOrUpdate(modelCateogry);
return _categoryMapper.CreateCategory(modelCateogry);
}
}
}
But when I add The "Product" table which has a foreign key of the Category table, the product controller doesn't work and throws below exception:
No session bound to the current context
ProductController class is as follow:
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using TestMVCProject.Web.Api.HttpFetchers;
using TestMVCProject.Web.Api.Models;
using TestMVCProject.Web.Api.TypeMappers;
using TestMVCProject.Web.Common;
//using TestMVCProject.Web.Common.Security;
using NHibernate;
namespace TestMVCProject.Web.Api.Controllers
{
[LoggingNHibernateSession]
public class ProductController : ApiController
{
private readonly ISession _session;
private readonly IProductMapper _productMapper;
private readonly IHttpProductFetcher _productFetcher;
public ProductController(
ISession session,
IProductMapper productMapper,
IHttpProductFetcher productFetcher)
{
_session = session;
_productMapper = productMapper;
_productFetcher = productFetcher;
}
public IEnumerable<Product> Get()
{
return _session
.QueryOver<Data.Model.Product>()
.List()
.Select(_productMapper.CreateProduct)
.ToList();
}
public Product Get(long id)
{
var product = _productFetcher.GetProduct(id);
return _productMapper.CreateProduct(product);
}
public HttpResponseMessage Post(HttpRequestMessage request, Product product)
{
var modelProduct = new Data.Model.Product
{
Description = product.Description,
ProductName = product.ProductName
};
_session.Save(modelProduct);
var newProduct = _productMapper.CreateProduct(modelProduct);
//var href = newproduct.Links.First(x => x.Rel == "self").Href;
var response = request.CreateResponse(HttpStatusCode.Created, newProduct);
//response.Headers.Add("Location", href);
return response;
}
public HttpResponseMessage Delete()
{
var categories = _session.QueryOver<Data.Model.Product>().List();
foreach (var product in categories)
{
_session.Delete(product);
}
return new HttpResponseMessage(HttpStatusCode.OK);
}
public HttpResponseMessage Delete(long id)
{
var product = _session.Get<Data.Model.Product>(id);
if (product != null)
{
_session.Delete(product);
}
return new HttpResponseMessage(HttpStatusCode.OK);
}
public Product Put(long id, Product product)
{
var modelProduct = _productFetcher.GetProduct(id);
modelProduct.ProductName = product.ProductName;
modelProduct.Description = product.Description;
_session.SaveOrUpdate(modelProduct);
return _productMapper.CreateProduct(modelProduct);
}
}
}
and the mapping class for Product table:
using TestMVCProject.Data.Model;
using FluentNHibernate.Mapping;
namespace TestMVCProject.Data.SqlServer.Mapping
{
public class ProductMap : ClassMap<Product>
{
public ProductMap()
{
Id(x => x.ProductId);
Map(x => x.ProductName).Not.Nullable();
Map(x => x.Description).Nullable();
Map(x => x.CreateDate).Not.Nullable();
Map(x => x.Price).Not.Nullable();
References<Category>(x => x.CategoryId).Not.Nullable();
}
}
}
What is wrong?
Your snippets are missing the way, how the ISessionFactory is created and how ISession is passed into your controllers... You should follow this really comprehensive story (by Piotr Walat):
NHibernate session management in ASP.NET Web API
Where you can see that we, can use 2.3. Contextual Sessions:
NHibernate.Context.WebSessionContext - stores the current session in HttpContext. You are responsible to bind and unbind an ISession instance with static methods of class CurrentSessionContext.
The configuration
<session-factory>
..
<property name="current_session_context_class">web</property>
</session-factory>
In the article you can check that we need at the app start initialize factory (just an extract):
public class WebApiApplication : System.Web.HttpApplication
{
private void InitializeSessionFactory() { ... }
protected void Application_Start()
{
InitializeSessionFactory();
...
Next we should create some AOP filter (just an extract):
public class NhSessionManagementAttribute : ActionFilterAttribute
{
...
public override void OnActionExecuting(HttpActionContext actionContext)
{
// init session
var session = SessionFactory.OpenSession();
...
public override void OnActionExecuted(HttpActionExecutedContext actionExecutedContext)
{
// close session
...
session = CurrentSessionContext.Unbind(SessionFactory);
}
For more details check the source mentioned above
Your approach of passing the session to the constructor of the controller factory does not seems to be working, there are a few ways to do this
1. Using dependency injection
If you are using a dependency injection framework, you have to configure controller so that it's constructed per request, it should looks like this (I have used the code for Ninject)
Step 1 - setup the session for injection
public class DIModule : NinjectModule
{
public override void Load()
{
this.Bind<ISessionFactory>()... bind to the session factory
this.Bind<ISession>().ToMethod(ctx => ctx.Kernel.Get<ISessionFactory>().OpenSession())
.InRequestScope();
}
private ISession CreateSessionProxy(IContext ctx)
{
var session = (ISession)this.proxyGenerator.CreateInterfaceProxyWithoutTarget(typeof(ISession), new[] { typeof(ISessionImplementor) }, ctx.Kernel.Get<SessionInterceptor>());
return session;
}
}
Step 2 - Create the controller factory so that it will inject the session when resolving
public class NinjectControllerFactory : DefaultControllerFactory, IDependencyResolver
{
private IDependencyResolver _defaultResolver;
public NinjectControllerFactory(IDependencyResolver defaultResolver)
{
_defaultResolver = defaultResolver;
}
protected override IController GetControllerInstance(RequestContext requestContext, Type controllerType)
{
return controllerType == null
? null
: (IController)DependencyKernel.Kernel.Get(controllerType);
}
public IDependencyScope BeginScope()
{
return this;
}
public object GetService(Type serviceType)
{
try
{
return DependencyKernel.Kernel.Get(serviceType);
}
catch (Exception)
{
return GetService(serviceType);
}
}
public IEnumerable<object> GetServices(Type serviceType)
{
try
{
object item = DependencyKernel.Kernel.Get(serviceType);
return new List<object>() {item};
}
catch (Exception)
{
return GetServices(serviceType);
}
}
public void Dispose()
{
}
}
Step 3 - Register the controller factory
public class MvcApplication : System.Web.HttpApplication
{
protected void Application_Start()
{
var factory = new NinjectControllerFactory(GlobalConfiguration.Configuration.DependencyResolver);
ControllerBuilder.Current.SetControllerFactory(factory);
GlobalConfiguration.Configuration.DependencyResolver = factory;
}
}
Now what will happen is that when your controller is created it will inject the a new NH session per each request.
2. Using a filter
This is much simpler, but you may need to change your controllers a bit this to work,
Step 1 - Setup the correct session context for the factory
_sessionFactory = CreateConfiguration()
.ExposeConfiguration(c => c.SetProperty("current_session_context_class","web"))
.BuildSessionFactory();
Step 2 - Create the filter
public class SessionPerRequestAttribute : ActionFilterAttribute
{
public override void OnActionExecuting(HttpActionContext actionContext)
{
var session = SessionFactory.OpenSession();
NHibernate.Context.CurrentSessionContext.Bind(session);
base.OnActionExecuting(actionContext);
}
public override void OnActionExecuted(HttpActionExecutedContext actionExecutedContext)
{
var session = SessionFactory.GetCurrentSession();
session.Flush();
session.Clear();
session.Close();
base.OnActionExecuted(actionExecutedContext);
}
}
Step 3 - Register the filter in global configuration
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
//Do other config here
config.Filters.Add(new SessionPerRequestAttribute());
}
}
Step 4 - Modify your controller a bit,
public class CategoryController : ApiController
{
private readonly ICategoryMapper _categoryMapper;
private readonly IHttpCategoryFetcher _categoryFetcher;
public CategoryController(
ICategoryMapper categoryMapper,
IHttpCategoryFetcher categoryFetcher)
{
_categoryMapper = categoryMapper;
_categoryFetcher = categoryFetcher;
}
public IEnumerable<Category> Get()
{
var session = SessionFactory.GetCurrentSession();
return session
.QueryOver<Data.Model.Category>()
.List()
.Select(_categoryMapper.CreateCategory)
.ToList();
}
}
Here what happens is, when a request comes it will create a new session and it is bound to the request context and same is used for the web API method.
I have one controller that takes a username and pass and checks against a database. IF the user is authenticated, I want to call an overloaded action on another controller.
My end goal is to authenticate a user against an old table from a MySQL db (I have this part working). Once the user is authenticated, I would like to be able to "automagically" forward the person to the built in MVC registration page but I would like to populate some fields in the view using data obtained from the first controller (the old databse info).
When I try something like what I have below I get an error about the Register() methods being ambiguous. I've also tried using the [ActionName("Register2")] attribute but then the error returned says it cant find a method named Register2.
public class MigrateAccountController : Controller
{
OldUserRepository oldDb = new OldUserRepository();
public ActionResult Index()
{
return View();
}
[HttpPost]
public ActionResult Index(User u)
{
if (oldDb.isValid(u.username, u.password))
return RedirectToAction("Register", "Account", u);
return View(u);
}
}
public class AccountController : Controller
{
public IFormsAuthenticationService FormsService { get; set; }
public IMembershipService MembershipService { get; set; }
protected override void Initialize(RequestContext requestContext)
{
if (FormsService == null) { FormsService = new FormsAuthenticationService(); }
if (MembershipService == null) { MembershipService = new AccountMembershipService(); }
base.Initialize(requestContext);
}
public ActionResult Register(User u)
{
return View(u);
}
public ActionResult Register()
{
ViewBag.PasswordLength = MembershipService.MinPasswordLength;
return View();
}
}
First thing you cannot have the same action name on the same controller that is accessible on the same verb. You need to either change the action name or use a different HTTP verb:
public class AccountController : Controller
{
public IFormsAuthenticationService FormsService { get; set; }
public IMembershipService MembershipService { get; set; }
protected override void Initialize(RequestContext requestContext)
{
if (FormsService == null) { FormsService = new FormsAuthenticationService(); }
if (MembershipService == null) { MembershipService = new AccountMembershipService(); }
base.Initialize(requestContext);
}
[HttpPost]
public ActionResult Register(User u)
{
return View(u);
}
public ActionResult Register()
{
ViewBag.PasswordLength = MembershipService.MinPasswordLength;
return View();
}
}
and in order to pass data between actions, well, if you are using GET, you could pass them as query string parameters when redirecting.
Or IMHO a better way would be not to redirect in this case but simply return the corresponding view by passing it the proper view model:
[HttpPost]
public ActionResult Index(User u)
{
if (oldDb.isValid(u.username, u.password))
{
return View("~/Account/Register.aspx", u);
}
return View(u);
}
You can use the TempData values in this case.